In a Fight, Don’t Count on Smiley

By Daniel Akst

Smile and the world smiles with you. Or at least that’s the hope many of us have in a confrontation.

Humans aren’t the only ones to invest such hopes in a smile. A show of teeth is a sign of submission or non-aggressive intentions across species. So what are we to make of fighters who smile in pre-match photos?

We can assume they’re more likely to lose, at least according to a fascinating new study by psychologists Michael W. Kraus and Teh-Way David Chen. They studied pre-fight photos of 152 mixed martial arts fighters and data on their performance from 2008 and 2009. By a variety of standards, a more intense smile in a pre-match photo predicted bad things for a fighter. As the researchers put it:

. . . fighters showing more neutral pre-fight facial expressions in photographs standing opposite of their opponent were more likely to win the fight, more likely to end the fight by knockout or submission, more likely to land a higher percentage of significant strikes, and more likely to wrestle their opponent to the ground during the fight. Also aligning with our central prediction, fighters showing more intense smiles were more likely to be knocked down by their opponent, were more likely to have their opponent land more significant strikes on them (i.e., they were punched and kicked more), and were more likely to be wrestled to the ground by their opponent during the fight.

As Kraus and Chen observe, the smile is a much-studied facial expression, one long associated with reduced physical dominance.

Men with elevated basal testosterone levels tend to have more masculine facial features, and to smile less in posed yearbook photos, in relation to men with lower basal testosterone levels (Dabbs, 1997; Mazur & Booth, 1998). Other work in naturalistic settings suggests that people tend to smile more when they are lower in social status (e.g., younger of age) than their interaction partners

Smiling, of course, is also about happiness, and outside the context of confrontation they are predictors not just of current mood but various future outcomes. The authors note, for instance, that high school students with more intense smiles in their yearbook photos reported higher well being years later.